Dambure Liyanage Sumangala Dias joined the Sri Lanka Air Force on 13th December 1984 as an Officer Cadet in the General Duties Pilot Branch in the 13th Officer Cadet intake. On completion of the Basic and Advanced phases of flying training, he was commissioned as a Pilot Officer in the GDP branch on 15th August 1986.

Air Vice Marshal Dias has completed his Staff Course at the Defence Services Staff College in Wellington, India in 2001 and completed National Defence Course in Mirpur, Bangladesh. He has also completed Junior Command and Staff Course in India, Joint Air Warfare Course at IAF, India and Air Craft Accident Investigation Course, Pakistan.

On 21st October 1996 he was appointed as the Commanding Officer of the No 02 Heavy Transport Squadron at Sri Lanka Air Force Base Ratmalana and subsequently as the Commanding Officer of the No 08 Light Transport Squadron at Sri Lanka Air Force Base Ratmalana. On successful completion of Staff College he returned to flying duties and took over as the Commanding Officer of No 06 Helicopter Squadron at Sri Lanka Air Force Base Vavuniya on 26th June 2002. On 01st June 2005 he was appointed as the Base Commander Sri Lanka Air Force Base Hingurakgoda which consists of three lodger formations including two helicopter squadrons. He was also appointed as the Senior Air Coordinator for the Humanitarian Operations and actively performed duties with the ground commanders located in North and East theaters (57, 58 and 58 Divisions) until the completion of the Humanitarian Operations in year 2009. On 05th December 2009 he was appointed as the Base Commander Sri Lanka Air Force Base Ratmalana which consists of six lodger formations including two flying squadrons, where he completed number of development projects including an international standard rugby ground. He was appointed as the Base Commander Sri Lanka Air Force Base Katunayake which consists of twenty five lodger formations including three flying squadrons for the period from 30th April 2012 to 10th June 2013. He was appointed as the Chief Flight Safety Officer and subsequently as the Deputy Director Air Operations in the year 2013. He was appointed as the Deputy Director Logistics on 28th February 2014 and became the Director Logistics on 01st July 2014. On 15th June 2016 Air Vice Marshal Dias was appointed as the Acting Director Air Operations of the Sri Lanka Air Force.

Air Vice Marshal DLS Dias was appointed the Chief of Staff of the Air Force w.e.f 01 October 2016

He was the first Chairman of SLAF Tug of War in 2011. He was the Chairman SLAF Athletic in 2012. Presently he is the Chairman SLAF Cycling.

Air Vice Marshal DLS Dias is married to Mayuri and blessed with two children, Bimsara and Visaka.